Flash 4 KD-SW4x1 4-Channel Video Switcher
Video
switching, either in a display or in an external unit, is a reality with
today's complex home theater systems. Multiple video sources often pose
a common problem that can only be solved by adding a video switcher into
the system. The risk of degrading the video signal becomes an unfortunate
issue that must be addressed. Quality video switching does not come cheaply
and after spending thousands on a high-definition display, few users are
willing to cut corners if it means compromising picture quality. Key Digital
Systems, known for their cost effective video products has introduced
the Flash4, a high-bandwidth 4-to-1
video switcher that works with both component (YPrPb) and RGB video signals.
The Flash4 is only 4 inches deep, but is designed to fit nicely into a
standard 19" rack (ears included). The front panel is simple with
a power light and four blue lights indicating the active input channel.
An input selector button sequentially switches through the four video
inputs connected to the unit.
The
inside of the Flash4 is a clean multi-layer printed circuit board. Surface
mount technology helps reduce parasitic capacitance and inductance. This
is particularly important with high-bandwidth video signals. The split-plane
circuit board design separates the digital interface electronics from
the video switching to keep high frequency noise out of the video signals.
Overall, we were impressed with the internal build quality of the Flash4
product. Video bandwidth rolls off -3dB at 140MHz, which ensures HDTV
signals will not be degraded. All common SDTV and HDTV scan rates are
supported with the Flash4.
Each
of the four channels has six RCA connections to accommodate either component
(YPrPb), RGB or RGB/HV video signals. When component video or RGB video
with sync-on-green is connected, three of the six inputs are used for
video. The remaining three inputs can be used for two channel analog audio
and a PCM digital signal. If RGB video with separate HV signals are connected
then only a PCM digital audio signal can also be switched. Each
of the three video component inputs (YPrPb or RGB) as well as the PCM
digital input is properly terminated with 75 ohms to prevent reflections.
The two inputs used for left and right analog audio or the horizontal
and vertical drive signals in the case of RGB video have high input impedance.
There's also a standard 9-pin RS232
serial interface that can be used to select any input on the Flash4 when
combined with an external controller. Power is supplied by an external
AC adapter that works with any voltage between 100-240VAC for universal
support.
The
IR remote included with the Flash4 video switcher is a standard sized
unit. The remote has a lot of buttons, but the majority of them are not
used. The first four numbers on the remote are used to select the input
to the display. The Channel Up/Down buttons can also be used to select
the inputs.
Our setup included a reference InFocus ScreenPlay 7200 high definition projector and a 100" Stewart FireHawk filmscreen mounted on a Luxus Deluxe frame. We fed analog video to the projector from several sources. Two set-top boxes were connected to the Flash4 switcher along with our JVC HM-DH30000U D-VHS high-definition VCR and HTPC. HDNet's Bikini Destinations on D-VHS produces an excellent reference picture with low noise and rich colors. Skin tones and fine detail remained accurate with or without the Flash4 in the video chain. We saw similar results with both set-top boxes and the HTPC. The transparency of the video switcher is very important and the Key Digital Flash4 appeared to deliver both functionality and performance whether video was 720p or 1080i. We saw no video degradation when using the Flash4.
Summary
The Key Digital System's Flash4 video switcher proved to be a quality
product that introduced no noticeable video degradation in our setup.
The unit offers flexibility by supporting both component and RGB video
systems. The ability to also switch PCM digital and two channel analog
audio when used with component video sources makes this product even more
attractive.
- Kevin
Nakano
